diff --git a/src/Network/Wai/SAML2.hs b/src/Network/Wai/SAML2.hs
--- a/src/Network/Wai/SAML2.hs
+++ b/src/Network/Wai/SAML2.hs
@@ -13,6 +13,7 @@
     -- * Callback-based middleware
     --
     -- $callbackBasedMiddleware
+    Result(..),
     saml2Callback,
 
     -- * Vault-based middleware
diff --git a/test/Spec.hs b/test/Spec.hs
new file mode 100644
--- /dev/null
+++ b/test/Spec.hs
@@ -0,0 +1,75 @@
+--------------------------------------------------------------------------------
+-- SAML2 Middleware for WAI                                                   --
+--------------------------------------------------------------------------------
+-- This source code is licensed under the MIT license found in the LICENSE    --
+-- file in the root directory of this source tree.                            --
+--------------------------------------------------------------------------------
+
+module Main ( main ) where 
+
+--------------------------------------------------------------------------------
+
+import Control.Concurrent
+import Control.Monad.IO.Class
+
+import qualified Data.ByteString as BS
+import qualified Data.ByteString.Lazy as LBS
+import qualified Data.Vault.Lazy as V
+import Data.X509
+import Data.X509.File
+
+import Network.HTTP.Types.Status
+import Network.Wai
+import Network.Wai.Test
+import Network.Wai.Handler.Warp
+import Network.Wai.SAML2
+
+--------------------------------------------------------------------------------
+
+-- | 'tests' implements the tests.
+tests :: Session ()
+tests = do
+    samlResponse <- liftIO $ BS.readFile "test-data/sample-response"
+
+    let req = (setPath defaultRequest "/sso/assert"){
+        requestMethod = "POST",
+        requestHeaders = [("Content-Type","application/x-www-form-urlencoded")]
+    }
+
+    res <- srequest $ SRequest req (LBS.fromStrict samlResponse)
+
+
+    samlResponseWithRs <- liftIO $ BS.readFile "test-data/sample-response-with-rs"
+
+    res <- srequest $ SRequest req (LBS.fromStrict samlResponseWithRs)
+
+    assertStatus 200 res 
+
+-- | 'main' is the main entry point for the test suite.
+main :: IO ()
+main = do
+    -- load private and public keys for the SP and IdP respectively
+    [privKey] <- liftIO $ readKeyFile "test-data/sp.pem"
+    [pubKey] <- liftIO $ readSignedObject "test-data/idp.pem"
+
+    let (PrivKeyRSA privateKey) = privKey
+    let (PubKeyRSA publicKey) = certPubKey $ signedObject $ getSigned pubKey
+
+    -- construct a configuration for the SAML2 middleware; we disable
+    -- time validation since it would require us to issue new responses
+    -- every time we run the tests
+    let config = (saml2Config privateKey publicKey){ 
+        saml2DisableTimeValidation = True 
+    }
+
+    -- run the middleware with a basic application on top and execute the
+    -- tests against it
+    runSession tests $ saml2Vault config $ \req respond -> do 
+        print $ V.lookup relayStateKey (vault req)
+        respond $ case V.lookup errorKey (vault req) of 
+                Just err -> do 
+                    responseLBS status400 [] "Invalid request"
+                Nothing -> 
+                    responseLBS status200 [] "Hello World"
+
+--------------------------------------------------------------------------------
diff --git a/wai-saml2.cabal b/wai-saml2.cabal
--- a/wai-saml2.cabal
+++ b/wai-saml2.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 0ab786ffa39a1a85044697458c860145df0f561c8b7ba0211f4fc6718c81d5ef
+-- hash: f63d7b16c92954665cf67b0990eb0619c871dcf428ad23f9674aa34050d6ad9d
 
 name:           wai-saml2
-version:        0.2.1.0
+version:        0.2.1.1
 synopsis:       SAML2 assertion validation as WAI middleware
 description:    A Haskell library which implements SAML2 assertion validation as WAI middleware
 category:       Security
@@ -61,6 +61,39 @@
     , vault >=0.3 && <1
     , wai >=3.0 && <4
     , wai-extra >=3.0 && <4
+    , x509 <2
+    , x509-store <2
+    , xml-conduit <2
+  default-language: Haskell2010
+
+test-suite wai-saml2-tests
+  type: exitcode-stdio-1.0
+  main-is: Spec.hs
+  other-modules:
+      Paths_wai_saml2
+  hs-source-dirs:
+      test
+  default-extensions: OverloadedStrings MultiWayIf RecordWildCards FlexibleInstances
+  ghc-options: -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base >=4.8 && <5
+    , base64-bytestring >=0.1 && <2
+    , bytestring >=0.9 && <0.11
+    , c14n >=0.1.0.1 && <1
+    , cryptonite <1
+    , data-default-class <1
+    , http-types <1
+    , mtl >=2.2.1 && <3
+    , tasty
+    , tasty-hedgehog
+    , tasty-hunit
+    , text <2
+    , time >=1.9 && <2
+    , vault >=0.3 && <1
+    , wai >=3.0 && <4
+    , wai-extra >=3.0 && <4
+    , wai-saml2
+    , warp
     , x509 <2
     , x509-store <2
     , xml-conduit <2